Fate x stay night: New Contract
by Archdemon Slayer
Summary: Kirei has broken his pact with his Servant. About to fade, Caster must find a new Master soon so he can carry out his revenge against the priest. Some Grand Order, some Servant classes are switched, including Lancer's. Will be a high T-rating for now, but it will go up to M later.
1. Day 1 I

**This has some things from Fate/Grand Order: First Order like Cu Chulainn being Caster and Medusa being Lancer. The Rider is Alexander the Great from Fate/Zero.**

 **This IS a fourth route for Fate/stay night.**

 **Even with some minor changes, just go with it. And during the 3rd night, Rin was on the rooftop because she sensed the faint presence of a Servant, and was going there to check it out after school had been let out.**

* * *

The Holy Grail War. Every 60 years, seven mages are chosen to be Masters. Each summons a Heroic Spirit, known as a Servant, to fight for them. The Servants fall into one of the seven classes.

Saber.

Archer.

Lancer.

Rider.

Caster.

Assassin.

Berserker.

Once all seven of the Servants in each of these seven classes are summoned, the seven Masters fight to the death in the city of Fuyuki in Japan. The last Servant-Master pair left standing is awarded the Holy Grail, a cup able to grant any wish of the Master and Servant. Each Servant has a chance of winning. Even if they lack another's raw power, they can still win a battle against an enemy Servant by outsmarting them. It has been 10 years since the end of the last War. The fifth one is soon to begin...

* * *

The Church was a dark place. Only a few candles and the moonlight lit the area. A priest with short brown hair, brown eyes, and wearing a Church uniform faced the podium at the front of the room. In his left hand, he held an open book. This man was known as the Overseer for the War. Unknown to others, he was a Master in the War as well.

Behind him and to his right, a man sat in one of the front pews. His left arm was slung over the back of the pew. The man had blonde hair and a black jacket over a white shirt. He looked human in those cases, but he also had red eyes with serpentine pupils. Even the air around him gave off the impression that he wasn't human.

"Where is the dog known as Caster? He has been absent from the Church for a few days," the man said. The priest closed the book and stood up straight. He replied without turning.

"I sent him out to gather information on the other competitors. The other day, a girl named Rin Tohsaka informed me that she had summoned an Archer Servant. I need Caster to check out her Servant's fighting abilities once the school she attends lets out. I instructed him to let out only enough mana for her to detect it and draw her in. If she's smart, she'll wait until dusk falls to check it out. Like with the other Servants, Caster will fight it to ascertain it's fighting abilities."

The first chuckled. "By showing himself to the others, his chances of winning the War will be lessened."

"It does not matter how his chances will be once the final Servant is summoned. His job is simply to give me information on the others. That way, your chances of winning the War will be greater, Gilgamesh."

"You slayed his original Master. What was her name? Bazett? You promised him another chance to win. And now you're going back on your word and throwing him away?"

"Despite how I see him, he is still a Servant in this War. Depending on how he fights in it will determine whether or not he will have a chance of winning. Bazett simply was not able to make full use of his abilities. She would have been killed along with him right away. It seemed like such a waste to allow someone like him to die right away. That is why I stole Bazett's Command Seals and became Caster's Master instead. However, his use to me will come to an end once he reports to me on the fighting abilities of the Saber."

"What will you do with him then, Kotomine?" Gilgamesh asked. The priest grinned.

"I will break my pact with him so I am free to make a new one with you. Will that be acceptable?"

"It will be, but the problem will be Caster's action towards you after the pact is broken. He still harbors a grudge towards you for killing his original Master. Once he has been freed, he will most likely kill you."

"That is why I will ensure my safety to you."

Gilgamesh sighed. "Very well. I will keep him from harming you. But what will you do for me in return?"

"I shall give you Caster's fate after I break my pact with him."

Gilgamesh raised an eyebrow. "What do you mean by that?"

"To prevent himself from fading away, he will rush to make a new pact with another Master. If he grows attached to that person, ripping that joy away from him will be amusing. I shall allow you to witness his despair at losing his Master a second time at the hands of the same man."

Gilgamesh laughed. "You never cease to keep me amused, Kotomine! It shall bring me great joy to watch that dog suffer."

Kotomine turned around so he was facing the other man. The priest smirked. "I had hoped that would be satisfactory to your tastes."

Gilgamesh was still chuckling. "Very well. If you can promise me that, I shall allow you to give me orders during this War."

* * *

The night was still, save for a car that occasionally went down a road. No one who happened to be out driving paid any attention to the figure leaping over rooftops. The figure was a man. However, his clothing suggested he wasn't from this era. He wore a grey-black shirt over his torso. Matching glove-like garments covered both of his arms. They cut off at the knuckles and only held onto his hands by the fabric over his palms. Armor ran down the length of the top of his arms and ended at the top of his hands. On the index finger on each hand was a silver ring. Over the shirt looked to be a light blue hooded poncho that wrapped around his back and over his arms. A white strap held both end together over the top of his chest. The garment itself cover over half of the man's torso and to the elbows of each arm. The ends looked tattered. The hood was lined with white fur over the edges. The garment was over his long, blue hair with only the ends of it visible past the end of the garment. Over his waist was a white belt holding the white cloth under it up. Beneath the cloth was what looked to be the bottom of a cloak. Like the other garment, it was light blue. Over his shins were metal guards and on his feet were sandals.

However, he didn't seem human just like Gilgamesh. Like that man, he had red eyes with serpentine pupils. Long, silver earrings hung from each ear. Even the air around him gave off the impression that he wasn't a person, but rather some kind of beast. The scent he gave off suggested that as well. He wasn't human, but a Servant. He was Cu Chulainn, a Servant that fell into the Caster class.

Caster wasn't happy. He had to fight two Servants in one night. During the one against Archer, there had been a witness, a red-haired boy who ran inside the school building to avoid Caster as the Servant hunted the boy down. He finally caught up to the kid on the third floor. The lad had ran fast, but was no match for the speed of a Servant. He fired a spell at the boy, boring a hole through the kid's chest. That should've killed him. But later that night, Caster had to kill the same person. The lad had fought back with rolled-up paper, but it must've been strengthened. The lad blocked each swing of Caster's staff like he was holding a sword. The kid had jumped into glass to the outside trying to get away from the Servant, but Caster's kick sent him flying near the shed. The kid struggled to his feet and ran inside the shed. He turned around just past the doorway and unrolled the paper like a shield, trying to block a downward swing from Caster's staff, which was covered in flames. The paper couldn't withstand it and burst, floating through the air as white scraps.

He was about to finish the lad off once and for all when a blinding white light filled the room. He had just enough time to block something swung at him with his staff and was thrown out of the shed. It turns out that the kid he was trying to kill was a Master. He had blocked something completely invisible, which he assumed was a sword, by the kid's newly-summoned Servant, Saber. Not only had she been able to react fast enough to avoid an arm of Wicker Man, it gave away his true name to her. Right then, Kirei called for him to return to the Church. He left Saber with a threat as he retreated, bounding over rooftops towards the bridge.

He growled as he headed for the Church. Even though he had been ordered by Kirei to only analyze the other six Servants' strengths, it seemed that Saber's Master was unable to give her enough mana for her to use her full strength, thus it should have been easy to kill her. It would mean one less person they had to fight in this War.

It was strange, though. Kirei was revealing Caster to all of the other Servants, so now they all know what to expect from him, eliminating the element of surprise. Why would Kirei do this? Did he have some plan that the Servant hasn't been made aware of?

He finally reached his destination. The Church loomed before him, feeling dark and foreboding. All was silent, save for the noise one cricket was giving off. Inside gave off the feeling of the place being a dungeon instead of a church. No lights were on. Only the moonlight filtering through the windows cast long shadows from the pillars and pews as it spilled over the floor. His own footsteps echoed off the walls, alerting the false priest at the front of the room of his presence.

The man's voice sent chills up Caster's spine. "Ah, Caster. I'm glad you have finally showed up. Now you can explain to me why you used your Noble Phantasm."

"The seventh Servant, a Saber, appeared," Caster replied. "She caught me by surprise. I was left with no other choice but to use it. We were in a stalemate otherwise."

Kirei sighed. "You know you should be prepared for anything." He looked at Caster. "How are her fighting abilities?"

"She fights close-quarters with an invisible object, most likely a sword."

Out of sight of Caster, Gilgamesh perked his head up. An invisible sword? It's hard to believe she would be summoned two Wars in a row, but that must be her.

"Anything else?" Kirei asked.

"Not much, but she is incredibly strong. I also got the feeling her Master, the boy ya ordered me to kill, was unable to give her enough mana fer her to use her full power. Despite that, she managed to keep me on my toes while I was fightin' her."

"Very well." Then Kirei grinned. "You're usefulness to me is gone now."

It took Caster a moment to process what Kirei said. "What do ya mean?!"

It happened in an instant. Several golden portals appeared around the Servant. Chains flew out of each of them, holding the man tight. They coiled all around him, holding his limbs, neck, and torso. He struggled to free himself, but to no avail. The chains wouldn't even budge. "What the hell is this?! The fuck are ya plottin'?!"

Kirei lifted the sleeve over his right arm. Caster's eyes widened. It was covered in Command Seals. He lifted it up, facing Caster. "By my Commend Seals, our pact is terminated."

One of the Seals flashed red before fading. Caster's body went limp as the mana that had been flowing into him was cut.

Kirei lowered the arm, letting his sleeve cover the Command Seals again. "Caster, I suggest you flee from here right away and find a new Master before you vanish. Also, don't even think about attacking me. I do have another Servant, and I will order him to kill you if you attack."

The chains vanished and Caster fell onto the floor on all fours, breathing heavily. "Ya...were workin'...with...another Servant...this whole time..?!"

Kirei folded his hands behind his back. "It will be amusing to see how much you struggle throughout the rest of this War. The next time we meet, I expect you to be ready to fight me to the death."

Caster chuckled. "Don't get...too full of yerself...Kotomine...Even like this...I could...kill ya easy..."

"Unless you want to die, you shouldn't do that just yet. Now get out of here. I sense Tohsaka and another approaching the Church."

"...Fine." Blue mana started to cover his body. "But never stop watchin' yer back, 'cuz I'll be comin' fer ya!"


	2. Day 1 II

**January 14-18 was HELL for me! I was getting the laptop screen I fucked up (check out chapter 21 in Fate/Xillia for what happened.) replaced, but after my dad took off the screen to put in a new one, it wasn't the right size. So we had to order another. Until it came in, I couldn't use my laptop. And I had an idea for this chapter and it was KILLING me that I couldn't type it.**

 **Btw, I saw one review. I will make Medusa in the Lancer form she had in First Order with her Rider parameters. She'll have her Grand Order weapon.**

 **Master-Servant pairs will be as follows:**

 **Shirou - Arturia/Saber**

 **Rin - EMIYA/Archer**

 **Souichirou - Kojirou/Assassin. Will be actual Assassin Servant with some new attacks**

 **Shinji - Medusa/Lancer**

 **Waver - Iskander/Rider**

 **Illya - Hercules/Berserker**

 **Akiko (OC) - Cu Chulainn/Caster**

 **Kirei - Gilgamesh/Archer**

 **Note: Kirei is able to use the Dragon Tooth Warrior familiars.**

 **I have read bits and pieces of the visual novels, so please forgive any inaccuracies.**

 **What first got me into Fate was that I liked what Ufotable did with Tales. So I looked up what anime they were involved with making. I saw Fate (Don't remember it all, but at that time it was probably the announcement of them making Fate/stay night: Unlimited Blade Works.) I looked up Fate/stay night on Youtube and looked at the first episode. Except the animation didn't look like Ufotable's. A few days later, I found out was looking at the DEEN version. It still threw me off it for a few years. Then I saw Ufotable's while I was bored in the hospital (Full details about my brain injury in my profile page.) I got sucked into it.**

* * *

A Bounded Field had been set up around the Church. Anyone who came within range was detected. However, this didn't work for Servants. Kirei had Gilgamesh keeping watch for once. (He usually had Caster do it.) While Kirei was telling Saber's Master, Shirou, about the Holy Grail War, Gilgamesh was watching Saber while the knight was standing by the gate, wearing a yellow cloak. He had seen her face while Rin led Shirou into the Church. He could hardly believe it. It was her! She had indeed returned in this War.

Once the two humans left the Church, Saber followed them up the street. As soon as they were out of sight, Gilgamesh hopped out of the tree he had been hiding in and went inside the building. It still looked as dark and gloomy as ever, only the light of a candle outlining Kirei. Gilgamesh sat in one of the pews to the left of the false priest and relaxed his legs on top of the seat as he reclined himself back.

"I got a look at the Saber's face. She is indeed the same one from the Fourth War," the man said.

"I suspected as much," Kirei replied. "That Master who summoned Saber is called Emiya as well."

Gilgamesh raised his eyebrows. "Someone with the same name as Kiritsugu? It must not be a coincidence then that he was able to summon Arturia."

Kirei looked at him. "Indeed. Meeting him makes me feel as though I've been reunited with Kiritsugu."

"So are you going to seek to destroy him as well?"

"I'm not as interested in that as making Caster suffer. However, I foresee a confrontation between myself and the boy in the future. After talking to him, he seems to share Kiritsugu's ideals."

"Speaking of that dog Caster, I wonder if he has succeeded in finding a new Master," Gilgamesh said.

"He needs to soon. After having his pact broken, he will only last a couple of hours before vanishing. Though sleeping and eating will prolong this, he won't stand a chance against me without someone to supply him with mana."

"It seems to me like quite a gamble," Gilgamesh pointed out. "Mages are rare, after all. And even if he finds one, that person needs to be powerful enough with magic to qualify as a Master. Besides, mages don't use their powers within the view of others."

"Do not worry. Since it is dark, there won't be many to be a witness to someone using magic. Besides, all mages give off a small amount of mana that can be faintly detected. A few days ago, I found someone with the potential to be a Master. I will have my familiars draw Caster's attention to that mage."

Gilgamesh smirked. "Mongrel he may be, at least he is good for entertainment."

"I know. That's why I plan to make him suffer."

* * *

Caster was searching all over for a mage that could qualify to be a Master. However, he had to search from the rooftops of buildings so he wouldn't draw attention to himself. Since night had fallen, there weren't too many people on the streets. Maybe he could ask the Master of Archer for help if he got to the point where he was getting desperate. Problem was that he didn't know her name or where she lived. She also wasn't likely to help an enemy Servant. And Archer pisses him off by just breathing.

Caster was waiting on a rooftop in the shopping district. There was a dark alleyway in between the one he was on and the next one. The only lights came from windows and the street lamps. Then he saw something odd. There was a woman on the sidewalk on the same side of the street that the building the Servant was on top of was on. He could only see that she had long, silver hair. She wore a black shirt with openings over each shoulder, white shorts, and black boots that went up to her knees. On her legs were two black bands just over and under her knees. Red strips of vertical cloth connected them and went under her shorts and boots. She turned her head and broke into a run. Chasing after her were bone familiars that were used by Kirei.

The woman was running into a dark alleyway. Caster didn't know at that time, but it was so anyone nearby wouldn't see what she was going to do. She held out both hands. In the right one, fire formed into her palm. In the left was lightning.

She sprang forward and smashed both palms into the skeleton familiar. The alleyway was lit up as the magic exploded, the familiar crumbling into dust. She stood up and another jumped at her from her blind spot. Without thinking, Caster jumped down from the rooftop, slamming the butt of his staff into the golem's head. Fire burst from the end and the familiar was engulfed in flames. When they died down, the burnt golem had already turned into a pile of dust.

Caster heard footsteps coming from behind him and he turned his head. The lass was looking at him nervously, twiddling her thumbs. "U-um...thanks for helping..."

Caster faced her. "Don't worry 'bout it." Now that he could see her up close, he noticed she had bright blue eyes. "I take it you're a mage then?"

"Um y-yeah...Um, not to be rude, but you look like you're in the wrong century..." The man wore a strange outfit. He was holding a staff in his right hand. Golden parts were over the wooden handle. The top was wooden and perpendicular to the handle. On the top was a magic circle. At the end of the head was a ring going through a small hole in the wood. On it were three feathers.

He scratched the back of his head. "Let's just go somewhere away from anyone who might be eavesdroppin'. I'll explain everythin' there."

The girl sighed. "Fine, whatever. But you'd better explain everything! Let's talk at my place."

The girl led and Caster followed. She seemed to be taking him out of the shopping district and into the residential area. Only street lamps and the light from the half moon in the night sky lit up the streets. It was quiet, not even the noise of night creatures filling the air. The girl turned and walked up to one of the houses. No lights were shining through the windows. It was a one-story house. Only a single tree was in the yard. There were signs on the trunk of the wood being hit, some looking fresher than others.

The girl took a key out of her pocket and put it into the lock right over the knob. After she turned the key, something clicked and she took the key out, putting it back into her pocket. She grabbed the knob and turned it, the door opening. She stepped inside and flipped a switch on the wall near it. Light flooded the house, revealing the mat she was on. She took off her boots and placed them to the left of it. This allowed Caster to see that at the end of the red strips were black bands around her ankles. She went further inside, Caster following her. A closet with the white doors shut over it was to the right of the doorway, on the wall perpendicular to it. Right in front of the mat, there was a section where you would have to step up. Several steps forward took you to the living room. The outside of the house looked Japanese-styled, but the inside looked Western. On the right wall in the living room was another entryway into a hall. However, a little bit to the side of it was a black leather couch up against the wall. A coffee table was right in front of it and a table with a lamp on top of it was to the left of the couch. Across from it was a large table with a video player and a T.V. on top of it. The table was to the right of the entryway into the kitchen. To the left was a bookshelf filled with books and framed pictures. On the wall on the far end of the room was a large window.

The woman walked into the living room and plopped down on the couch's left cushion. She patted the spot next to her for Caster to sit. He made his staff vanish and sat down to her right. She spoke first.

"Okay, so what the hell is going on with why you look so out of place?"

"It may be hard fer ya to believe, but I'm a hero from the past."

She looked at him like he had grown a second head. "You're right; I don't believe it. Sure you look like you're from a different century, but give me a good reason why I should even begin to believe you're from the past!"

Caster sighed. This was gonna be hard. "Alright, let's just start off simple. Ya know 'bout the Holy Grail?"

"Not a ton, but I at least know that it's an ancient artifact capable of making miracles happen."

"Basically. Every sixty years, it allows fer seven Heroic Spirits known as Servants to be summoned by seven mages to fight one another. The last pair standin' wins the Grail an' is allowed a wish to be granted."

The woman crossed her arms. "It all sounds like bullshit to me. There's no way that- -" Then her eyes widened. She had read that around 200 years ago, three mage families tried to summon the Holy Grail and ended up fighting one another. The Grail was a source of high magic, able to do anything. It made sense for other battles for it to break out over the years. It was possible then that this man was telling the truth. But still... "Even if what you're saying is true, why tell me?"

"'Cuz I need a new Master. An' I'm wonderin' if ya would do it."

"A Master? Why do you need one?"

"Servants need to be supplied mana from their Master to stay in this world. Bein' without one, only the mana I have is keepin' me here. But it won't last fer much longer."

"Say I do it, what's the catch?"

"Ya'll be pulled into the Holy Grail War, the fight to the death between Masters an' Servants. Also, I'm lookin' fer revenge. I'll help ya out in the war after I carry it out."

"Revenge? Against who?"

"Just someone who killed my original Master. Will ya make a pact with me?"

The mage sighed. "Fine, I'll do it. But how do I do it?"

"Just hold out yer right hand to me an' ya'll know."

The woman did as she was told. As she did, words flowed through her head and she began speaking without realizing it. "Hear me. My will creates your body and your sword carves my destiny! If you heed the Grail's call and submit yourself to my will and my reason, then answer! And hearing your answer, I shall entrust my fate to your sword!"

"On my honor as a Caster, I accept ya as my new Master."

The woman winced and gripped her right hand as pain flared into it. When she pulled her other hand away, she saw what looked to be a red tattoo on the back of it. In the center was what looked to be a hollow diamond with the left and right sides curved. And on both sides were two shapes in a U. It had spikes along the outside, but was smooth on the inside.

She was staring at it. "What's this?"

"Those are yer three Command Seals. They're proof of our pact. They allow ya to force yer Servant to perform a specific action or teleport. Ya only have those three fer the whole War. Once ya use all of 'em, yer no longer a Master."

"So you're my Servant now?"

"Yeah. I'm a Caster-class Servant, Cu Chulainn. What should I call you?"

"My name is Akiko Hashomoto. Just call me Akiko."

"Very well. I shall call ya Akiko. By the way, do ya have a wish ya want the Holy Grail to grant?"

Akiko was silent. She was staring at one of the pictures on the bookshelf. It showed two older people, a man and woman, holding a little girl. The silver hair and blue eyes showed that it must be Akiko from when she was younger. "...I'll ask for it to bring my parents back to life..."

"What do ya mean by that?"

However, Akiko didn't hear him. Her mind was elsewhere, thinking about 10 years ago, when she was 14.

 _There was fire everywhere. The air stank of burning buildings and death. The smoke filled her nostrils and made her almost pass out. She didn't hear the twin cries of her name. Only one though was going through her head._

 _It's hot._

 _It's hot._

 _It's hot._

 _And she couldn't move._

 _Sparks flew through the air as another beam of the Hashomoto's burning house hit the ground._

 _Someone please make it stop!_

 _She couldn't take it anymore!_

 _"Akiko!"_

 _It was a voice she didn't recognize._

"Akiko!"

Caster was shaking her, trying to snap her out of her daze. Akiko shook the memory from her head. "Sorry about that."

"Look, if it upsets ya, I won't press fer details on yer wish. Just get some rest. Don't worry; I'll keep watch."

"Thanks Caster. When I feel ready, I'll tell you."

"Just don't freeze up when we go to New City tomorrow."


End file.
